docs: complete F-Droid readiness checks

[zefutoff]

Summary

• mark the Phase 5 F-Droid metadata and reproducibility checks as complete

Validation

The signed-release workflow has now been successfully exercised on main.

Successful workflow run:

38289574019

Validated commit:

96ac98b

The workflow successfully:

• installed Android Build Tools 34.0.0
• signed the release APK with the expected release certificate
• rebuilt the unsigned APK from a clean clone
• reconstructed the signed APK with apksigcopier
• compared the upstream and reconstructed APK byte-for-byte
• generated and validated the runtime SBOM
• uploaded the signed release artifact

Both signed APKs produced:

82a9dd4b1ce9aa13a90d12926b9318c903053b0b370697240ae0654c777cd1d0

Result:

F-Droid reproducibility check: IDENTICAL

Roadmap

Completes:

F-Droid metadata and reproducibility checks

The next Phase 5 item is:

Review Android package namespace before stable release